563
FXUS63 KOAX 112304
AFDOAX

Area Forecast Discussion
National Weather Service Omaha/Valley NE
604 PM CDT Tue Jun 11 2024

.KEY MESSAGES...

- Staying warm into next week. Heat index values could approach
  or exceed 100 in at least parts of the area Wednesday,
  Thursday, Sunday, and Monday.

- Our next chances for stronger to severe storms arrive
  Wednesday (northeast Nebraska) and Thursday (southeast
  Nebraska and southwest Iowa).

- Details remain unclear, but we`ll have daily storm chances
  Friday into next week with potential for strong to severe
  storms at times.

&&

.DISCUSSION...
Issued at 328 PM CDT Tue Jun 11 2024

Early afternoon analysis showed a cold front continuing to sag
south into southern NE and far southwest IA, with a few cumulus
clouds bubbling up along it. Can`t completely rule out a few
sprinkles along the front as we go through the
afternoon/evening, but should be very few and far between if
they develop at all. Otherwise, despite the front, it was still
pretty warm across the area, with temperatures as of 3 PM in the
mid 80s to around 90.| Heading into tonight, will have to keep
an eye on potential shower and storm development across north-
central into northeast NE as low level moisture transport ramps
up and points into that area. Guidance is in decent agreement
that we see some development on the nose of said moisture
transport, but there remains spread on just how far north the
development would be, with some guidance suggesting it all
remains in SD. For what it`s worth, there does appear to be at
least some decent deep layer shear for storm organization,
though instability should remain somewhat limited (around 1000
J/kg of MUCAPE). Still, can`t completely rule out a stronger
storm sliding southeast down the CAPE gradient into northeast NE
during the early morning hours Wednesday (maybe a 10-20%
chance).

For the daytime hours Wednesday, expect strengthening southerly
flow to usher in our fair share of warm, moist air into the
area, with highs in the mid to upper 90s, possibly 100 in a few
spots and dewpoints in the mid 60s. As a result, expect heat
index values to approach or exceed 100 in some locations. In
addition, this will lead to a fairly unstable airmass across the
region, with 11.12Z HREF mean SBCAPE values of 2500-3000 J/kg.
This will be ahead of an approaching cold front, currently off
the Pacific Northwest coast. Expect storm development as the
front moves in, though latest guidance suggests the
front/strongest forcing will largely remain to our north and
east through the afternoon hours, meaning we`ll have pretty weak
forcing in our area. Instead, we may have to rely on broad warm
air advection and/or reaching the convective temperature
(around 100) or maybe an outflow boundary from early day
convection to get anything to go in northeast NE. Should
something develop in the afternoon, large hail, damaging winds,
and localized flooding would be the primary threats. The surface
front does eventually dive south into our are Wednesday
evening, but guidance differs quite a bit regarding how far west
any development will extend. Most CAMs keep storms to our east,
but a few pieces of guidance suggest a few storms could move
along the MO River before midnight.

The front looks to stall out somewhere in vicinity of the NE/KS
border by late Thursday afternoon. This will provide a focus
for additional strong to severe storms Thursday
afternoon/evening. Overall model trends are to keep the front
and storm activity just to our south, or perhaps clip Pawnee and
Richardson counties, but still some time for things to change.
Once again, large hail, damaging winds, a locally heavy
rain/flooding would be the primary threats. Otherwise, it will
be another warm to hot day Thursday, especially south of the
front where highs are expected to be in the mid 90s to around
100 once again. Areas to the north are expected to top out in
the mid 80s to lower 90s.

Friday will be slightly cooler as remain north of the front and
dewpoints will remain in the 50s. Most of the day should stay
dry, but storm chances look to return by Friday evening and
overnight as a fairly strong shortwave slides through and brings
our best chance for widespread storms in the forecast period.
Still some questions on exact timing of this wave as well as how
much instability will be in our area, but still should be a
decent shot of rain for most. Precip could continue on and off
into Saturday, but guidance still suggests some decent
instability will be able to nose into the area by Saturday
afternoon ahead of the primary shortwave trough axis moving
through Saturday evening. This will bring perhaps our next best
shot at strong to severe storms, but there will be a lot of
smaller scale details to work out between now and then.

We`ll remain in an active pattern heading into next week with
southwesterly flow aloft and various bits of shortwave energy
sliding through and interacting with a surface boundary draped
somewhere across the area to bring shower and storm chances.
Basically, expect at least pop-up showers and storms somewhere
in or very near the area nearly every day next week. In
addition, we`ll remain warm and humid with highs mostly in the
upper 80s to mid 90s through at least Monday, though precip on
any given day will certainly play a role in those temperatures
for some.

&&

.AVIATION /00Z TAFS THROUGH 00Z WEDNESDAY/...
Issued at 601 PM CDT Tue Jun 11 2024

VFR conditions through the period. Light and variable winds at
TAF issuance, becoming southerly by 02z around 5-7 knots.
Southerly winds increase to 16 knots with gusts to 27 knots by
14-15z. There is a 20% chance of shower or storm at KOFK 12-16z,
but too low to include in the forecast at this time.

&&

.OAX WATCHES/WARNINGS/ADVISORIES...
NE...None.
IA...None.

&&

$$

DISCUSSION...CA
AVIATION...DeWald